[pypy-commit] pypy default: Add a warning about comparing strings with ``is``.

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: 
Changeset: r74608:677120906bff
Date: 2014-11-20 11:34 +0100
http://bitbucket.org/pypy/pypy/changeset/677120906bff/

Log:	Add a warning about comparing strings with ``is``.

diff --git a/pypy/doc/cpython_differences.rst b/pypy/doc/cpython_differences.rst
--- a/pypy/doc/cpython_differences.rst
+++ b/pypy/doc/cpython_differences.rst
@@ -297,6 +297,9 @@
 above types will return a value that is computed from the argument, and can
 thus be larger than ``sys.maxint`` (i.e. it can be an arbitrary long).
 
+Notably missing from the list above are ``str`` and ``unicode``.  If your
+code relies on comparing strings with ``is``, then it might break in PyPy.
+
 
 Miscellaneous
 -------------